Endothelium mediated vasorelaxant effects of Ca(2+)-ATPase inhibitors on thoracic aorta from neonatal and adult guinea pigs.
Vasorelaxant effects of Ca(2+)-ATPase inhibitors were examined in the isolated adult and neonatal guinea pig thoracic aorta focusing on the functional alterations of endothelial cells with development. Cyclopiazonic acid produced an endothelium-dependent vascular relaxation in the adult aorta preconstricted with norepinephrine, whereas no relaxant response was obtained by the compound in the neonatal preparation. Endothelium-dependent vascular relaxation was also produced by another Ca(2+)-ATPase inhibitor, thapsigargin, in the adult aorta, but not in neonatal ones. The endothelium-dependent vascular relaxations produced by both Ca(2+)-ATPase inhibitors were suppressed either by NG-nitro-L-arginine or by methylene blue, suggesting that nitric oxide (NO) mediated the endothelium-dependent vascular relaxations. The present results suggest the possibility that mechanisms underlying the synthesis and/or release of NO change with development in the guinea pig aortic endothelial cells.
Tanaka
H
H
Department of Pharmacology, Toho University School of Pharmaceutical Sciences, Chiba, Japan.
Taniguchi
H
H
Agata
N
N
Tanaka
Y
Y
Shigenobu
K
K
D000375:Aging / Q000502:physiology*; D000818:Animals; D000831:Animals, Newborn; D001013:Aorta, Thoracic / Q000187:drug effects / Q000254:growth & development; D000252:Calcium-Transporting ATPases / Q000037:antagonists & inhibitors*; D004730:Endothelium, Vascular / Q000187:drug effects / Q000502:physiology*; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D005260:Female; D006168:Guinea Pigs; D066298:In Vitro Techniques; D007211:Indoles / Q000494:pharmacology; D008297:Male; D009126:Muscle Relaxation / Q000187:drug effects; D009131:Muscle, Smooth, Vascular / Q000187:drug effects / Q000502:physiology*; D009638:Norepinephrine / Q000037:antagonists & inhibitors / Q000494:pharmacology; D019284:Thapsigargin / Q000494:pharmacology; D014662:Vasoconstrictor Agents / Q000037:antagonists & inhibitors / Q000494:pharmacology
D004791:Enzyme Inhibitors; D007211:Indoles; D014662:Vasoconstrictor Agents; D019284:Thapsigargin; D000252:Calcium-Transporting ATPases; D009638:Norepinephrine; C000543:cyclopiazonic acid